JPS614892A - Two cylinder rotary compressor - Google Patents

Abstract

PURPOSE:To increase the range of controlling capacity and save energy consumption by providing a bypass controlling means on one cylinder of a two- cylinder rotary compressor and a suction blockage controlling means on the remaining cylinder. CONSTITUTION:A controlling means which bypasses a gas which has been compressed halfway in a cylinder 3a, through a suction passage 11a by the operation of a control valve 18, is provided in one cylider of a two-cylinder rotary compressor. On the otherhand, a control valve 21 which closes a suction passage, is provided on the suction passage 11b of the remaining one cylinder, enabling suction blockage control. Since bothn of the cylinders are connected in parallel, it is possible to carry out capacity control in four stages as a whole by the use of both of the control valves 18, 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a capacity-controlled two-cylinder rotary compressor.

[Prior art]

FIG. 1 is a vertical cross-sectional view showing a conventional two-cylinder rotary compressor, and FIG. 2 is a vertical cross-sectional view showing the suction passage and its surroundings. In the figure, 1 is a drive mechanism having eccentric parts 1a and 1b. A barrel drive shaft 12.13 is a compression element driven by the drive shaft 1, and the compression elements 12 and 13 are composed of parts 1 to 14. That is, 28t2b is the compression chamber 3a concentric with the drive shaft 1.

The cylinder 4a and 4b are driven by the eccentric parts 1a and 1b of the drive shaft 1 to form the cylinder 2a.
A rolling piston, 5a, 5b, which rolls along the inner wall of the ring piston 4a, 5b, and a vane, 6a, which is pressed against the outer circumference of the ring piston 4a, 4b, and divides the compression chambers 3a, 3b into a low pressure chamber and a high pressure chamber. 6b is the cylinder 2a, 2
The vane springs 7 and 8, which are mounted in the interior of the vane springs 7 and 8 and press the vanes 5a and 5b, have one end of the compression chambers 3a and 3b closed, and are provided with bearings (not shown) on which the drive shaft 1 is supported. 9 is the two cylinders 2a, 2b
This is an intermediate partition plate that is interposed between them to separate the compression chambers 3a and 3b. In addition, 10 is a storage container in which two compression elements 12.degree.
118t11b is a suction bow (14a, 14) provided in the cylinder 2a, 2b and serving as a suction part of the compression element 12.13.
The suction passage 11a communicates with the suction pipe 1 and the suction passage 11a communicates with the suction pipe 1 through a communication hole 9a provided in the intermediate partition plate 9.
It is connected to 1.

In the two-cylinder rotary compressor configured as described above, when the drive shaft 1 is rotated, the rolling pistons 4a and 4b roll along the inner walls of the cylinders 2a and 2b, as shown by the arrows in FIG. Low pressure refrigerant gas flows from the suction pipe 11 to the suction passages 11a, 11b and the suction port) 14a? 14b
The low-pressure refrigerant gas is passed through the compression chambers 3a and 3b, and the sucked low-pressure refrigerant gas is compressed in the compression chambers 3a + 3b to become high-temperature and high-pressure refrigerant gas, which is then stored through a discharge pipe (not shown). A refrigeration circuit (not shown) connected to the outside of the container 10 is supplied. In the above-mentioned refrigeration circuit, the load that needs to be cooled is cooled by high-temperature, high-pressure refrigeration gas. However, such conventional two-cylinder rotary compressors are not suitable for applications where the rotation speed of the drive shaft is variable, such as in automobiles. If the rotation speed of this drive shaft is increased, the amount of refrigerant discharged per unit time will increase, resulting in overcooling.Also, even if the rotation speed of the drive shaft is constant, when the temperature is relatively low, overcooling will occur. This has the disadvantage that extra power is consumed or the frequency of turning the compressor on and off increases, which impairs the comfort of air conditioning.

[Summary of the invention]

The present invention aims to eliminate the drawbacks of the conventional two-cylinder rotary compressor as described above, and has a compressed gas bypass system for one of the two compression elements,
The other compression element is equipped with a low-pressure refrigerant gas suction cutoff system and its own capacity control mechanism, so the combined operation allows for
A two-cylinder rotary compressor is provided in which the discharge capacity can be changed in four stages, thereby making it possible to save energy consumption without sacrificing cooling comfort.

[Embodiments of the invention]

FIG. 3 is a cross-sectional view showing compression elements on the upstream side of the low-pressure refrigerant gas flow of a two-cylinder rotary compressor according to an embodiment of the present invention, and 1 to 14 are the conventional 2-air 1v rotary compressor. It is exactly the same as a compressor. Reference numeral 15 denotes a bypass hole serving as a bypass means provided on the inner peripheral surface of the cylinder 2a, and this bypass hole 15 is communicated with the cylinder suction passage 11a through a bypass passage 16. The bypass hole 15 and the bypass passage 16 are communicated with each other by a bypass passage opening/closing hole 17, and as shown in FIG. A sliding member that can slide in the longitudinal direction of the bypass passage opening/closing hole 1T and has a part of its outer circumferential surface cut out.
8, and a resilient member is provided between the slider 18 and the end plate 7 so that a force is applied to the slider 1B from the direction of the end plate 7 toward the intermediate partition plate 9, which is the partition member. 19 is accommodated. Further, the slider 18 is slid in the bypass passage M opening/closing hole 17, and the bypass passage opening/closing means opens and closes the bypass passage M@16, so that the bypass passage and the bypass hole 15 are connected to each other, that is, the compression chamber of the cylinder 2a. A partial notch is provided on the outer periphery so that the inside of the cylinder 3a and the cylinder suction passage 11a are communicated or closed. moreover,
A side of the passage opening/closing hole 17 opposite to the side to which the spring 19 is attached is communicated with the high pressure side through a high pressure pipe 20.

Figure 5 shows how the compression elements downstream of the low pressure refrigerant gas stream are controlled, with (a) the suction boat open and (b) the downstream compression element of the low pressure refrigerant gas stream being controlled. The suction port of the element is shown in a closed state, and there is a wall surface of the suction passage 11b in the suction passage 11b of the compression element 13 on the downstream side of the low-pressure refrigerant gas flow taken into the two-cylinder rotary compressor. A slider 21 that is capable of sliding in the longitudinal direction of the suction passage 11b with a small gap, and a slider 21 that moves from the direction of the intermediate partition plate 9, that is, from the direction in which refrigerant gas is sucked, to the end plate 8. slider 21 so that force is applied to
A spring 22 is housed between the intermediate partition plate 9 and the intermediate partition plate 9.

Further, the suction bow N 4b and the slider 21 are arranged so that the suction key 14b serving as the suction part is opened and closed by the suction passage opening/closing means in which the slider 21 slides on the suction passage 11b and the suction passage is opened and closed. Dimensions and shape dimensions are set for determining the position of. Further, the side of the slider 21 opposite to the side where the refrigerant gas is sucked is communicated with the high pressure side through a high pressure pipe 23.

FIG. 6 is a diagram showing control valves provided for controlling each compression element. A control valve 24 is provided at one end of the high pressure pipe 20 for controlling the compression element 12 on the upstream side of the low pressure refrigerant gas flow, and a control valve 24 is provided at one end of the high pressure pipe 20. A high pressure pipe 2 is used to control the compression element 130 on the downstream side of the refrigerant gas flow.
Control valves 25 are independently provided at one end of 3, high pressure gas is supplied from these high pressure pipes 20.23, and each compression element 12.13 is controlled by the operation of the control valve 24.25. Natsu C is here. This high pressure gas is
It is supplied from the high-pressure side of the refrigeration circuit, such as the discharge hose of the compressor or the service valve on the discharge side.

Next, 2 of an embodiment of the present invention configured as described in 1 or more.
The operation of the cylinder rotary compressor will be explained. In the compression element 12 on the upstream side of the low-pressure refrigerant gas flow, when the control valve 24 is in the closed state, the slider 1 is closed as shown in FIG.
8 is a resilient force of a spring 19, and the space between the bypass hole 15 and the bypass passage 16 is closed. In this state, drive shaft 1
When the compressor element 12 is rotated, the compression element 12 is operated normally and is in an operating state with a discharge capacity of 100%. When the control valve 24 is opened, high pressure gas is guided into the bypass passage opening/closing hole 17 through the high pressure pipe 20, and as shown in FIG. It is moved toward the end plate 7 side against the force, and the bypass hole 15 and the bypass passage 16 are communicated with each other.In this state, when the drive shaft 1 is rotated, the compression element 12 is moved so that the rolling piston 4a is moved toward the cylinder 2a. Up to the position of the bypass hole 15 provided on the inner periphery of the
The refrigerant gas in the cylinder 2a is returned to the suction passage 118 through the bypass hole 15 and the vibe entry passage 16, so it is not compressed, and the rolling piston 4a moves through the bypass hole 16.
Capacity control operation is started in which compression is started only after passing step 5. The rate of this capacity control varies depending on the position where the bypass hole 15 is provided, but if the position U of the vane 5a is 0°, the control rate is 50° at the position where the rotation angle of the crank M1 is approximately 220°. It has been confirmed through experiments that %.

Next, in the compression element 13 on the downstream side of the low-pressure refrigerant gas flow, when the control valve 25 is closed, (
As shown in b), ? The suction port N is arranged so that the eyelet 21 is communicated with the suction passage 11b by the elastic force of the spring 22.
4b is open. In this state, the compression element 13 operates normally.

When the control valve 25 is opened, high-pressure gas is guided from the high-pressure pipe 23, so that the slider 21 resists the elastic force of the spring 22 and closes the intermediate partition plate, as shown in (11) in FIG. 9 side, the suction boat 14b of the compression element 13 is closed, low-pressure refrigerant gas is not led into the cylinder 2b, and the compression element 13 is in cylinder operation in which it is not operated.

As described above, since the two compression elements 12 and 13 are each independently provided with a capacity control mechanism 4-j, the control valve 2
4 and control valve 25 are both closed.
A discharge capacity of 0% is indicated. When the control valve 24 is released and the control valve 25 is closed, only 50% of the operation is performed in the compressor element 12 on the upstream side of the low-pressure refrigerant gas flow, which corresponds to 75% of the total discharge capacity. Discharge ability can be obtained.

Next, when the control valve 24 is closed and the control valve 25 is opened, the compression element 13 on the downstream side of the low-pressure refrigerant gas flow is put into rest operation, so that the discharge capacity corresponds to 50% of the total discharge capacity. Ru.

Furthermore, when both control valves 24, 25 are opened,
Since the compression element 12 is operated at 50% and the compression element 13 is operated in the cylinder mode, the discharge capacity is equivalent to 25% of the total discharge capacity. These things are easier to understand according to the table below. In this table, V24. V25 is indicated by controls 24 and 25, respectively, and their opening and closing are indicated by symbols ○-2■, respectively.

Furthermore, in the two-cylinder rotary compressor of one embodiment of the present invention, by switching the two control valves, the discharge capacity corresponds to 100%, 75%, 50%, and 25% of the total discharge capacity. , the control rate of the compression element on the upstream side of the low-pressure refrigerant gas flow is 50 to enable four-stage capacity control operation.
%, but if the position of the bypass hole is changed, an arbitrary control rate can be obtained. For example, if the control rate of the discharge capacity of the above FE and compression element is set to 75%, the total discharge capacity will be 100%.
Needless to say, it depends on whether the four-stage capacity control M'NA provides a discharge capacity corresponding to , 85%, 50% or 35%.

〔Effect of the invention〕

As explained above, the present invention includes a bypass means provided in the housing of the upstream compression element of the two compression elements, and a bypass passage connecting the bypass means and the compressor suction passage. Since the passage opening/closing means is provided in the suction passage with which the suction part of the compression element on the downstream side communicates, capacity control operation is possible.
Operation according to the cooling load is possible, energy consumption can be reduced, and the frequency of on/off operations for controlling the compressor can be reduced, leading to improved cooling comfort.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing a conventional two-cylinder rotary compressor;
FIG. 2 is a longitudinal sectional view showing the suction passage and the vicinity of the suction passage of the two-cylinder rotary compressor 1 shown in FIG. FIG. 3 is a cross-sectional view showing a compression element on the upstream side of a low-pressure refrigerant gas flow of a two-cylinder rotary compressor according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line A-A in FIG. In the cut sectional views, (a) shows the bypass passage closed state, and (→ shows the bypass passage open state. In the M cross-sectional view showing the surrounding area (f
) shows the open state of the suction port of the compression element on the downstream side of the low-pressure refrigerant gas flow, and (b) shows the closed state of the suction port. FIG. 6 is FIG. 1 showing the capacity opening control valves of the upstream and downstream compression elements. In the figure, 1 is the ffJIIJ axis, 2 is the cylinder, 9 is the intermediate partition plate, 11 is the suction pipe, 11a and 11b are suction passages,
12 is a compression element, 13 is a compression element, and 14a. 14bl↑Suction boat, 15 is a bypass hole, 16 is a bypass passage, 17 is a bypass passage opening/closing hole, 18 is a slider,
19 is a spring, 20 is a high pressure pipe, 21 is a slider, 22 is a spring, 23 is a high pressure vibrator, 24 is a control valve, and 25 is a control valve. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1) A compression element on the upstream side and a compression element on the downstream side of the gas flow to be compressed are arranged in series and driven by one drive mechanism, and the suction portion of the two compression elements is is communicated with the suction pipe via the suction passage for the compressed gas, and a bypass means is provided in the middle of the compression process of the housing of the upstream compression element, and the bypass means and the suction passage of the compressor are connected to each other. A bypass passage is provided, the bypass passage is provided with a bypass passage opening/closing means, and a suction passage opening/closing means is provided in the suction passage through which the suction portion of the downstream compression element is communicated. A two-cylinder rotary compressor. 2) A two-cylinder rotary compressor, characterized in that the bypass passage opening/closing means uses a sliding member and a resilient member. 3) A two-cylinder rotary compressor, characterized in that the suction passage opening/closing means uses a sliding member and a resilient member.